Keep the cairo clipping region in sync with the Skia one.

skia/ext/platform_device_linux.h

Index: skia/ext/platform_device_linux.h
diff --git a/skia/ext/platform_device_linux.h b/skia/ext/platform_device_linux.h
index c23a4d8280970c1b4a23adce18eabd014ebcb7b1..2a08cc8a75858959533c552d6b6dcf16c1eac493 100644
--- a/skia/ext/platform_device_linux.h
+++ b/skia/ext/platform_device_linux.h
@@ -7,19 +7,19 @@
 
 #include "third_party/skia/include/core/SkDevice.h"
 
-typedef struct _cairo_surface cairo_surface_t;
+typedef struct _cairo cairo_t;
 
 namespace skia {
 
 // Blindly copying the mac hierarchy.
 class PlatformDevice : public SkDevice {
  public:
-  typedef cairo_surface_t* PlatformSurface;
+  typedef cairo_t* PlatformSurface;
 
   // Returns if the preferred rendering engine is vectorial or bitmap based.
   virtual bool IsVectorial() = 0;
 
-  virtual cairo_surface_t* beginPlatformPaint() = 0;
+  virtual PlatformSurface beginPlatformPaint() = 0;
 
  protected:
   // Forwards |bitmap| to SkDevice's constructor.